Magnetic stirring or mixing devices used for mixing fluids such as slurries, solutions or suspensions are commercially available in the market. Such magnetic stirrers generally employ a magnetic stir bar immersed in a liquid-filled container such as a beaker, and a rotating magnetic field to cause the stir bar to spin rapidly. The resulting spinning action stirs the liquid continuously. A magnetic stirrer typically includes the magnetic stir bar, a flat platform or base supporting thereon the container of liquid, and a rotating magnet assembly or set of stationary magnets disposed within the base to create the rotating magnetic field below the container. The magnetic stir bar is usually a bar magnet coated with a plastic, porcelain, or glass material to make it chemically inert.
Although true solutions do not usually require constant mixing, suspensions containing small particles (e.g., biological cells, micro-solids, protein) must be constantly mixed to prevent the particles from separating out over time due to gravitational settling, especially in enclosed containers. Absent constant mixing, uniformity in the concentration and distribution of the particles diminishes over time. Magnetic stirrers are particularly useful for maintaining uniform mixtures. However, it becomes problematic where the container is positioned or mounted on devices such as in a syringe pump assembly in a manner that access to the container by conventional magnetic stirrers is unavailable.
Accordingly, there is a need in the art to develop an apparatus for mixing contents enclosed within a container with enhanced flexibility and efficiency. There is a further need for such an apparatus that can be implemented for use with enclosed containers arranged in various embodiments and configurations including elongated containers such as syringes.